Answer:
80 telephones should be sampled
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of [tex]\pi[/tex], and a confidence level of [tex]1-\alpha[/tex], we have the following confidence interval of proportions.
[tex]\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
In which
z is the z-score that has a p-value of [tex]1 - \frac{\alpha}{2}[/tex].
The margin of error is of:
[tex]M = z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
89% confidence level
So [tex]\alpha = 0.11[/tex], z is the value of Z that has a p-value of [tex]1 - \frac{0.11}{2} = 0.945[/tex], so [tex]Z = 1.6[/tex].
How many telephones should be sampled and checked in order to estimate the proportion defective to within 9 percentage points with 89% confidence?
n telephones should be sampled, an n is found when M = 0.09. We have no estimate for the proportion, thus we use [tex]\pi = 0.5[/tex]
[tex]M = z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
[tex]0.09 = 1.6\sqrt{\frac{0.5*0.5}{n}}[/tex]
[tex]0.09\sqrt{n} = 1.6*0.5[/tex]
[tex]\sqrt{n} = \frac{1.6*0.5}{0.09}[/tex]
[tex](\sqrt{n})^2 = (\frac{1.6*0.5}{0.09})^2[/tex]
[tex]n = 79.01[/tex]
Rounding up(as 79 gives a margin of error slightly above the desired value).
80 telephones should be sampled
The volume V of a rectangular solid can be expressed as a formula in terms of the length L, width w, and height h. Solve this formula for w.
WE
(Simplify your answer.)
Please help :)
Answer:
[tex] W = \frac {V}{LH} [/tex]
Step-by-step explanation:
Let the length of the rectangle be LLet the width of the rectangle be WLet the height of the rectangle be HMathematically, the volume of a rectangular solid is given by the formula;
V = L * W * H
V = LWH
Making W the subject of formula, we have;
[tex] W = \frac {V}{LH} [/tex]
three friends, akira,bruno and carmela pooled thier money to start a lemonade stand. akria contributes $25, bruno contributed $20 and carmela contributed $35. after a month, thier lemoneade stand had earned 2000, and they want to distribute this money in the same ratio as the money that was invested. how many dollars will brouno recieve
plz explian
9514 1404 393
Answer:
$500
Step-by-step explanation:
Bruno's fraction of the total contribution was ...
Bruno / Total = $20/($25 +20 +35) = 20/80 = 1/4
Then Bruno's share of the earnings is this same fraction, so is ...
(1/4) × ($2000) = $500
in a school there are 650 girls. It is 26% of the whole students, how many boys are there in the school?
Answer:
Step-by-step explanation:
Frt7v6c87buhinjomp,l.;
A fish story: The mean length of one-year-old spotted flounder, in millimeters, is 127 with standard deviation of 22, and the mean length of two-year-old spotted flounder is 158 with a standard deviation of 23. The distribution of flounder lengths is approximately bell-shaped. Part 1 of 4 (a) Anna caught a one-year-old flounder that was 155 millimeters in length. What is the z-score for this length
Answer:
The z-score for this length is of 1.27.
Step-by-step explanation:
Normal Probability Distribution:
Problems of normal distributions can be solved using the z-score formula.
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.
One-year-old flounder:
Mean of 127 with standard deviation of 22, which means that [tex]\mu = 127, \sigma = 22[/tex]
Anna caught a one-year-old flounder that was 155 millimeters in length. What is the z-score for this length
This is Z when X = 155. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{155 - 127}{22}[/tex]
[tex]Z = 1.27[/tex]
The z-score for this length is of 1.27.
Wrap your foot by plastic cover. B. Directions: Read the sentences carefully. Write TRUE if the statement is True and FALSE if not. 16. Rain and dull clouds, windy blue skies, cold snow, and sticky heat are very different conditions, yet they are all weather. 17. A weather instrument is any type of measurement device that gives information about the weather. 18. Weather is the mix of events that happen each day in our atmosphere. 19. Weather is different in different parts of the world and changes over minutes, hours, days and weeks. 20. The four letters EW, SW, NE, SN represent the four directions: East West, South West, North East, and South North.
Answer:
16. false
17. True
18. True
19. True
20. false
Step-by-step explanation:
16. all terms are expressions of weather - except for cold snow. "snowfall" would be the weather condition. "snow" itself is the accumulated mass of snowflakes on the ground.
17. that is simply true. there is nothing really to explain.
18. the same as 17. that is the definition of weather.
19. yes, that is part of the explanation of the difference between weather and climate.
20. South North is NOT a direction. it kind of contradicts itself. and what is between South and North ? East and West. so, even from that perspective it is not clear.
overall, what kind of math question is that ? that is more for geography, Earth science, or meteorology or something like this.
what's the answer to this
Answer:
the volume = 1152cm^2
Step-by-step explanation:
> The volume of cylinder =4 spheres
> Volume of sphere = v= 4/3πr³
> radius =6cm
volume of 4 spheres =
[tex]v \: = 4 \times \frac{4}{3} \times \pi \times {6}^{3} \\ \\ v = 1152cm {2} [/tex]
Answer:
the unused volume is 18095,57cm cubed
in the diagram below, triangle PQR is similar to triangle STU. based on the diagram, select all the equations that are true.
Answer:
ACF
Step-by-step explanation:
angles must be equal since the triangles are similar
Two figures are known as similar figures if there the corresponding angles are equal and the corresponding sider is in ratio. The statement that are correct are x=35, y = 55, and z =90.
What are Similar Figures?Two figures are known as similar figures if there the corresponding angles are equal and the corresponding sider is in ratio. It is denoted by the symbol "~".
Given the ΔPQR is similar to ΔSTU, therefore, the statements that are correct about the two triangles are,
∠P = ∠S = x = 35°
∠Q = ∠T = y
∠R = ∠U = z = 55°
Since the sum of all the angles of a triangle is equal to 180°. For ΔPQR we can write,
∠P + ∠Q + ∠R = 180°
°35 + y + 55° = 180°
y = 180° - 55° - 35°
y = 90°
Hence, the statement that are correct are x=35, y = 55, and z =90.
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find 9 rational no. between 8/7 and 17/10.
Answer:
[tex]\dfrac{81}{70},\dfrac{82}{70},\dfrac{83}{70},\dfrac{84}{70},\dfrac{85}{70},\dfrac{86}{70},\dfrac{87}{70},\dfrac{88}{70},\dfrac{89}{70}[/tex]
Step-by-step explanation:
We need to find 9 rational number between [tex]\dfrac{8}{7}\ \text{and}\ \dfrac{17}{10}[/tex]
We make the denominators of both fractions same. So,
[tex]\dfrac{8}{7}\times \dfrac{10}{10}=\dfrac{80}{70}[/tex]
and
[tex]\dfrac{17}{10}\times \dfrac{7}{7}=\dfrac{119}{70}[/tex]
The rational number are:
[tex]\dfrac{81}{70},\dfrac{82}{70},\dfrac{83}{70},\dfrac{84}{70},\dfrac{85}{70},\dfrac{86}{70},\dfrac{87}{70},\dfrac{88}{70},\dfrac{89}{70}[/tex]
37. Two numbers are such that their
difference, their sum and their
product are in the ratio 1:7: 24.
Find the product of the
number.
Answer:
8 and 6
Step-by-step explanation:
Two numbers are such that their difference, their sum, and their product are to
each other as 1:7:24. Their product must equal what number?
:
Two numbers a & b
Let x = the multiplier
:
a - b = 1x
a + b = 7x
a * b = 24x
:
Add the 1st two equations
a - b = x
a + b = 7x
2a = 8x
a = 4x
or
x = .25a
:
a * b = 24x
Replace 24x; a = 4x therefore:
a * b = 6a
b = 6
;
Using the 1st equation
a - b = 1x
Replace b with 6 and x with .25a
a - 6 = .25a
a - .25a = 6
.75a = 6
a =
a = 8
:
Find the multiplier
a - b = x
8 - 6 = 2
:
Check this
a - b = 2 (1*2)
a + b = 14; (7*2)
a * b = 48: (24*2)
:
The numbers are 8 and 6; their products = 48
Please help me with the question; It is attached in the image
Answer:
The function that passes through (0, 0) is [tex]f(x) = \frac{1}{6}\cdot e^{2\cdot x^{3}} - \frac{1}{6}[/tex].
Step-by-step explanation:
Firstly, we integrate the function by algebraic substitution:
[tex]\int {x^{2}\cdot e^{2\cdot x^{3}}} \, dx[/tex] (1)
If [tex]u = 2\cdot x^{3}[/tex] and [tex]du = 6\cdot x^{2} dx[/tex], then:
[tex]\int {e^{2\cdot x^{3}}\cdot x^{2}} \, dx[/tex]
[tex]\frac{1}{6}\int {e^{u}} \, du[/tex]
[tex]f(u) = \frac{1}{6}\cdot e^{u} + C[/tex]
[tex]f(x) = \frac{1}{6}\cdot e^{2\cdot x^{3}} + C[/tex]
Where [tex]C[/tex] is the integration constant.
If [tex]x = 0[/tex] and [tex]f(0) = 0[/tex], then the integration constant is:
[tex]\frac{1}{6}\cdot e^{2\cdot 0^{3}} + C= 0[/tex]
[tex]C = -\frac{1}{6}[/tex]
Hence, the function that passes through (0, 0) is [tex]f(x) = \frac{1}{6}\cdot e^{2\cdot x^{3}} - \frac{1}{6}[/tex].
Which of the following is the value of a when the function (x) - 3|xlis written in the standard form of an absolute value
function?
Answer:1
Step-by-step explanation:2
2
The value of a when the function f(x) = 3|xl is written in the standard form of an absolute value function is 3.
What is meant by an absolute function ?An absolute function is defined as a function which consists of an algebraic expression that is within absolute value symbols.
Here,
The standard form of the absolute value function is written by,
f(x) = a|x|
Given that,
f(x) = 3|x|
Comparing this with the standard form, we get,
a|x| = 3|x|
Therefore, a = 3
Hence,
The value of a when the function f(x) = 3|xl is written in the standard form of an absolute value function is 3.
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A box has length 4 feet, width 5 feet, and height 8 inches. Find the volume of the box in cubic feet and in cubic inches.
Answer:
13.4 cubic feet and 23040 inches
Step-by-step explanation:
Answer:
In cubic feet = 13.3 ft^3 ...........or 13.33ft^3
In cubic inches = 23040in^3
Step-by-step explanation:
In cubic feet it becomes
4(5) = 20 feet ^2 ................but we need volume in feet
so 8 inches = .............2/3 of a foot = 0.666667
Answer therefore is (4) x (5) x (0.666667) = 13.32ft^3
In cubic inches it becomes
4 x 12 = 48 inches
5 x 12 = 60 inches
and 8 inches
48 x 60 x 8 = 23040 in^3
We check by squaring the divider
23040/12^3 = 13.333
We only square and square again to find a cube but to square once we do this with area too.
Area 1. = 4 x 5 = 20 feet^2
Area 2. = 48 x 60 = 2880 in ^2 / 12^2 = 20
Which action is not a step in using paperfolding to find the midpoint of a line segment?
1. Come up with an integer that is BIGGER than 10.
2. Come up with an integer that is SMALLER than 10.
3. Come up with an integer that is BIGGER than 0.
4. Come up with an integer that is SMALLER than 0.
I need help pleaseeee
Answer:
1) any number that is greater than ten is considered an integer bigger than ten: for example, 11, 12, 100, 1000000, etc.
2) any number that is smaller than ten is considered an integer smaller than ten: for example, 9, 8, 7, -100, -100000, etc.
3) any number that is bigger than zero is considered an integer bigger than ten: for example, 1, 2, 10, 100, 100000, etc.
4) any number that is smaller than zero is considered an integer smaller than zero: for example, -1, -2, -3, -10, -100000, etc.
Step-by-step explanation:
An integer is any whole number
Answer:
Step-by-step explanation:
integer bigger than 10 is 11
integer smaller than 10 is 9
integer greater than 0 is 1.
integer smaller than 0 is -1.
The value of y varies with x and z, and y=8, when x=4 and z=10. What is the value of y when x=5 and z=11
What two methods are the best choices to factor this expression?
18x2 − 8
Answer:
18x2 is 36 but you have to minus it so the answer is 28.
Kamala marked the price of a cosmetic item as Rs 400. She offered her customers a discount of 20% and made a loss of Rs 30, what was the actual cost of the item to her?
Answer:
350
Step-by-step explanation:
400- 80 ( 20% discount)
=320+30(loss)
=350
what is the value of x?
what is the value of y?
type in an integer or decimal
9514 1404 393
Answer:
x = 5.6y = 65Step-by-step explanation:
There are a couple of relations that are applicable to these questions.
the product of segment lengths of crossed chords is the same for both chordsthe angle formed at crossed chords is the average of the intercepted arc measures__
The segment lengths relation tells us ...
10x = 8×7 . . . . . . products of segment lengths are equal
x = 56/10 = 5.6 . . . . divide by 10
__
The value of y° is the average of the intercepted arcs:
y° = (85° +45°)/2 = 65°
_____
Additional comment
This diagram does not have enough information to allow computation of z. We would need to know the intercepted arc, or the length of the secant that meets tangent z.
A manufacturer is interested in the output voltage of a power supply used in a PC. Output voltage is assumed to be normally distributed, with standard deviation 0.25 volt, and the manufacturer wishes to test volts against volts, using units. In your intermediate calculations, use z-scores rounded to two decimal places (e.g. 98.76).
(a) The acceptance region is_____. Find the value of a.
(b) Find the power of the test for detecting a true mean output voltage of 5.1 volts.
Answer: hello your question was poorly written but i was able to the get missing parts online which enabled me resolve your question
answer:
a) a = 0.1096
b) 1.89 watts
Step-by-step explanation:
Std of output voltage = 0.25 volt
H0 : μ = 5 volts
Ha : μ ≠ 5 volts
n = 16
a) Acceptance region = 4.9 ≤ X ≤ 5.1
Determine the value of a
value of a = 0.0548 + 0.0548
= 0.1096
attached below is the reaming solution
note : a is a type 1 error
b) power of test
True mean output voltage = 5.1 volts
P = - 1.89 watts
power cant be negative hence the power of the test = 1.89 watts
Many electronics follow a failure rate described by an exponential probability density function (PDF). Solar panels are advertised to last 20 years or longer, but panels made in China are failing at a higher rate. The time-to-failure of this device is usually exponentially distributed with mean 13 years. What is the probability of failure in the first 5 years
Answer:
The right answer is "0.3193".
Step-by-step explanation:
According to the question,
Mean,
[tex]\frac{1}{\lambda} = 13[/tex]
[tex]\lambda = \frac{1}{13}[/tex]
As we know,
The cumulative distributive function will be:
⇒ [tex]1-e^{-\lambda x}[/tex]
hence,
In the first 5 years, the probability of failure will be:
⇒ [tex]P(X<5)=1-e^{-\lambda\times 5}[/tex]
[tex]=1-e^{-(\frac{1}{13} )\times 5}[/tex]
[tex]=1-e^(-\frac{5}{13})[/tex]
[tex]=1-0.6807[/tex]
[tex]=0.3193[/tex]
A machine has two components both of which have a lifespan, in months, that is exponentially distributed with mean 8. The lifespan of the two components are independent. Find the probability both components are functioning in 12 months.
Answer:
0.0498
Step-by-step explanation:
In this question,
x~exponential
we have
mean = 1/λ = 8
from here we cross multiply, when we do
such that
λ = 1/8
probability of x functioning in 8 months
= e^-λx
= e^-1/8x12
= e^-1.5
= 0.2231
i got this value through the use of a scientific calculator
then the probability that these two are greater than 12
= 0.2231²
= 0.04977
= approximately 0.0498
therefore the probability that both components are functioning in 12 months is 0.0498
The area of a square is increasing at a rate of 24 centimeters squared per second. Find the rate of change of the side of the square when it is 4 centimeters. The rate of change of the side is Number cm/sec.
Answer:
3cm/s
Step-by-step explanation:
Area of a square is expressed as:
A = L²
Rate of change of area is expressed as:
dA/dt = dA/dL•dL/dt
Given that
dA/dt = 24cm²/s
L = 4cm
Required
dL/dt
Since dA/dl = 2L
dA/dl = 2(4)
dA/dl = 8cm
Subatitute the given values into the formula
24 = 8 dL/dt
dL/dt = 24/8
dL/dt = 3cm/s
A student sees a newspaper ad for an apartment that has 1330. How many square meters of area are there
Answer:
[tex]Area = 123.55 m^2[/tex]
Step-by-step explanation:
Given
[tex]Area = 1330ft^2[/tex]
Required
Convert to [tex]m^2[/tex]
To convert from square feet to square meter, we simply divide by 3.281^2
So, we have:
[tex]Area = \frac{1330}{3.281^2}m^2[/tex]
[tex]Area = \frac{1330}{10.765}m^2[/tex]
[tex]Area = 123.55 m^2[/tex]
write the volume formula beside the solid figure
Answer:
cube(v=l×l×l)
cylinder (v= πr^2h)
cone(v=1/3πr^2h)
rectangular prism (v= area of base×lenght)
pyramid (v=1/3×area of base×h)
Step-by-step explanation:
Cube:-a^3
Cuboid:-lbh
Cylinder :-pi r^2h
Cone:-1/3pi r^2h
Please help Quick this is hard so you’ll get brainliest thank you so much
Answer:
number 1: no
number 2: no
number 3: no
Given: f(x) = x- 7 and h(x) = 2x + 3
Write the rule for f(h(xc)).
Answer:
[tex]f(h(xc)) = 2xc-4[/tex]
Step-by-step explanation:
Given
[tex]f(x) = x - 7[/tex]
[tex]h(x) = 2x + 3[/tex]
Required
[tex]f(h(xc))[/tex]
First, calculate h(xc)
If [tex]h(x) = 2x + 3[/tex]
Then
[tex]h(xc) = 2xc + 3[/tex]
Solving further:
[tex]f(x) = x - 7[/tex]
Substitute h(xc) for x
[tex]f(h(xc)) = h(xc) - 7[/tex]
Substitute [tex]h(xc) = 2xc + 3[/tex]
[tex]f(h(xc)) = 2xc + 3 - 7[/tex]
[tex]f(h(xc)) = 2xc-4[/tex]
Express the function as the sum of a power series by first using partial fractions. f(x)=x+62x2−9x−5
Answer:
[tex]\frac{x+6}{2x^2-9x+5}=-\sum_{n=0}^{\infty} [(-2)^{n}x^{n} + \frac{x^{n}}{5^{n+1}}][/tex]
when:
[tex]|x|<\frac{1}{2}[/tex]
Step-by-step explanation:
In order to solve this problem, we must begin by splitting the function into its partial fractions, so we must first factor the denominator.
[tex]\frac{x+6}{2x^2-9x+5}=\frac{x+6}{(2x+1)(x-5)}[/tex]
Next, we can build our partial fractions, like this:
[tex]\frac{x+6}{(2x+1)(x-5)}=\frac{A}{2x+1}+\frac{B}{x-5}[/tex]
we can then add the two fraction on the right to get:
[tex]\frac{x+6}{(2x+1)(x-5)}=\frac{A(x-5)+B(2x+1)}{(2x+1)(x-5)}[/tex]
Since we need this equation to be equivalent, we can get rid of the denominators and set the numerators equal to each other, so we get:
[tex]x+6=A(x-5)+B(2x+1)[/tex]
and expand:
[tex]x+6=Ax-5A+2Bx+B[/tex]
we can now group the terms so we get:
[tex]x+6=Ax+2Bx-5A+B[/tex]
[tex]x+6=(Ax+2Bx)+(-5A+B)[/tex]
and factor:
[tex]x+6=(A+2B)x+(-5A+B)[/tex]
so we can now build a system of equations:
A+2B=1
-5A+B=6
and solve simultaneously, this one can be solved by substitution, so we get>
A=1-2B
-5(1-2B)+B=6
-5+10B+B=6
11B=11
B=1
A=1-2(1)
A=-1
So we can use these values to build our partial fractions:
[tex]\frac{x+6}{(2x+1)(x-5)}=\frac{A}{2x+1}+\frac{B}{x-5}[/tex]
[tex]\frac{x+6}{(2x+1)(x-5)}=-\frac{1}{2x+1}+\frac{1}{x-5}[/tex]
and we can now use the partial fractions to build our series. Let's start with the first fraction:
[tex]-\frac{1}{2x+1}[/tex]
We can rewrite this fraction as:
[tex]-\frac{1}{1-(-2x)}[/tex]
We can now use the following rule to build our power fraction:
[tex]\sum_{n=0}^{\infty} ar^{n} = \frac{a}{1-r}[/tex]
when |r|<1
in this case a=1 and r=-2x so:
[tex]-\frac{1}{1-(-2x)}=-\sum_{n=0}^{\infty} (-2x)^n[/tex]
or
[tex]-\frac{1}{1-(-2x)}=-\sum_{n=0}^{\infty} (-2)^{n} x^{n}[/tex]
for: |-2x|<1
or: [tex] |x|<\frac{1}{2} [/tex]
Next, we can work with the second fraction:
[tex]\frac{1}{x-5}[/tex]
On which we can factor a -5 out so we get:
[tex]-\frac{1}{5(1-\frac{x}{5})}[/tex]
In this case: a=-1/5 and r=x/5
so our series will look like this:
[tex]-\frac{1}{5(1-\frac{x}{5})}=-\frac{1}{5}\sum_{n=0}^{\infty} (\frac{x}{5})^n[/tex]
Which can be simplified to:
[tex]-\frac{1}{5(1-\frac{x}{5})}=-\sum_{n=0}^{\infty} \frac{x^n}{5^(n+1)}[/tex]
when:
[tex]|\frac{x}{5}|<1[/tex]
or
|x|<5
So we can now put all the series together to get:
[tex]\frac{x+6}{2x^2-9x+5}=-\sum_{n=0}^{\infty} [(-2)^{n}x^{n} + \frac{x^{n}}{5^{n+1}}}[/tex]
when:
[tex]|x|<\frac{1}{2}[/tex]
We use the smallest interval of convergence for x since that's the one the whole series will be defined for.
Two cities,a and are mapped on the coordinate plane. How far apart are they from each other?
Answer:
[tex]\sqrt{97} \\ \sqrt{9^{2}+4^{2} }[/tex]
Step-by-step explanation:
Which of the following is the solution set of -2|x| < -8 {x | -4 > x > 4} {x | x < -4 or x > 4} {x | -4 < x < 4}
Answer:
the second one
Step-by-step explanation:
Consider the function f(x) = x2 and the function g(x) = 3x2. How will the graph of g(x) differ from the graph of f(x)?
Select the correct answer
The graph of g(x) is the graph of f(x) shifted to the left 3 units.
The graph of g(x) is the graph of f(x) stretched vertically by a factor of 3.
The graph of g(x) is the graph of f(x) compressed vertically by a factor of
The graph of g(x) is the graph of f(x) shifted up 3 units.
Answer:
Third Choice - The graph of g(x) is the graph of f(x) compressed vertically by a factor of 3
Step-by-step explanation:
x^2 is the the parent function, so it opens up with a normal compression.
Any number > (greater than) 1 as a coefficient of x will lead to a vertical compression (narrower parabola), while any number < (less than) 1 as a coefficient of x will lead to a vertical stretch (wider parabola).
So, 3x^2 would have to have to be a compressed parabola.
I hope this helps!
Answer:
The graph of g(x) is the graph of f(x) stretched vertically by a factor of 3.
Step-by-step explanation:
A vertical stretch or shrink of a function, kf(x), results from multiplying the entire function by a constant, k.
In this case, g(x) equals 3 times f(x). If k > 1, then the graph will be stretched vertically (along the direction of the y-axis) by a factor of k.
So, the graph of g(x) is the graph of f(x) stretched vertically by a factor of 3.
